Overshooting your target weight loss

[aharris2]

This happens to us every so often, but this time I want to understand it. Rolando always tells the dialysis staff exactly what weight to target. Lately, he has been coming off 1.5 kg lighter. We have checked our math and checked the staff's math and it is correct. When we ask how this is possible, first of all they look at us like we're crazy and then say that sometimes it is easier to pull fluid off than others and that's why the target is overshot -WHAT?

What is really happening? When they set the target fluid loss what are they really adjusting and how can more than the target amount of fluid simply come off? Thanks...

[jbeany]

It's more art than science sometimes.  Some of the clinic machines keep pulling a low level of fluid off constantly, no matter if the goal has been reached or not.  It's just how they are designed.   I remember the nurses at the clinic having to continue to give me saline throughout an entire run when I had less than .3 to come off - the machine kept draining me dry even though it was set for no UF.  The nurses are also correct about it being easier to pull some fluid than others - depends on where your body is currently storing it.  I think it pulls easier from soft tissue than muscle.  As long as your BP is fine, leaving lower than goal weight isn't a problem, and it also might mean that your dry weight is incorrect and needs to be lowered.

[Adam_W]

I've ended up below my target weight several times. Modern dialysis machines are quite accurate as far as fluid removal (before volumetric ultrafiltration, fluid removal goals were nothing more than guesswork), but the bottom line is everyone is different, and like jbeany said it often depends on where the fluid is in your body, and whether or not you are gaining or losing real weight.

Adam

[SpeedFleX]

I don't know how they do it where you're at but here: When I go and let's say I gained 0.5 kilos, they add another 0.5 kilos because extra saline , food and water intake. which makes 1 kilos, now if I don't drink anything or eat I will 100% go below my dry weight, because the body is still working and sweating a little which a lot of times is forgotten, when eating and drinking that gets my sweated water back up to a normal level. It also makes a big difference if you're under a blanket or not.

hope that made sense

[Hawkeye]

While it is true that it is easier to remove fluids from some people there can be mechanical issues at work here as well.  Depending on the brand of machine you are on turning the UF off doesn't completely stop the UF, it only slows it down to a vary small rate.  The other thing is if the UF draw rate is calibrated properly.  Even though the screen says one thing the pump may actually be doing another.  Say for instance the the springs inside the pump are wearing out.  The calibration setting for a new or rebuilt pump are going to be slightly off from a pump that needs to be replaced or rebuilt.  Replacing and rebuilding the pumps as well as recalibrating the machine with these new or rebuilt parts is something the biomed techs at your clinics should be doing as part of their preventative maintenance on the machines.

[goofynina]

Hawkeye, doesnt it matter if you've eaten alot of sodium as well?  Doesnt the body try to hold on to the fluid and that makes it harder to take off fluid as well? 

[Hawkeye]

Hawkeye, doesn't it matter if you've eaten alot of sodium as well?  Doesn't the body try to hold on to the fluid and that makes it harder to take off fluid as well? 

Yeah too much sodium will cause you to retain fluids better.  I was just pointing out an aspect most people may not know about that could cause variances.

[goofynina]

Hawkeye, doesn't it matter if you've eaten alot of sodium as well?  Doesn't the body try to hold on to the fluid and that makes it harder to take off fluid as well? 

Yeah too much sodium will cause you to retain fluids better.  I was just pointing out an aspect most people may not know about that could cause variances.

I was just checking to make sure i got my facts right, thanks for your info 

[carolynt]

I still do not understand about weight and water.  I still go to the bathroom so I dont have to watch my fluid intake as much.  But when I first started dialysis I had lost alot of weight and I just gain about 4 pounds back.  I dont know if they think that is water weight or as I told them I think it is real weight on me now that my appetite has come back. But whenever I leave there I am down 3 pounds (i cant figure out kilos) so I tell all my friends I have this great diet.  So is this a real weight loss or when I drink a glass of water the three pounds will come back.  Am I making any sense or have I lost some brain cells while on dialysis. Thanks.

[goofynina]

That is odd since you say you still urinate, maybe your not urinating enough to put out what you take in, hmmm, interesting yet confusing   

[aharris2]

I still do not understand about weight and water.  I still go to the bathroom so I dont have to watch my fluid intake as much.  But when I first started dialysis I had lost alot of weight and I just gain about 4 pounds back.  I dont know if they think that is water weight or as I told them I think it is real weight on me now that my appetite has come back. But whenever I leave there I am down 3 pounds (i cant figure out kilos) so I tell all my friends I have this great diet.  So is this a real weight loss or when I drink a glass of water the three pounds will come back.  Am I making any sense or have I lost some brain cells while on dialysis. Thanks.

(alene writing)
Nah Carolyn, what you say makes sense. Here yah go:
1. The machines have some minimum that they have to take off. At our unit it is 0.4 kg/hr which is about 0.9 lbs/hr. You say that you walk out 3 lbs lighter each time. Are you dialyzing about 3.5 hrs?

2. If you feel good after dialysis - not light headed, bp not crashing, then the 3 lbs removed was excess fluid. (This implies that your kidneys are not effectively removing fluid). If your weight gain was real weight you would feel bad after dialysis.

3. If you feel bad, tell them to increase your dry weight or simply, not to take so much off. Even though the machine has a minimum, fluid can be replaced at regular intervals during dialysis.

4. If your kidneys are not effectively removing fluid then, yes, your 3 lbs will come back (after about 6 eight ounce drinks)

5. The metric system ... ooh ahhh!!!
1 kg = 1 liter = 1000 cc - oh, so pretty! But not so pretty 1 kg = 2.2 lbs
We'll do the kg to lbs conversion from time to time, but stick with liters (after all, soda  comes in a two liter bottle.)

 

[aharris2]

So here it is, another dialysis day. We walked in at 84.4 kg wanting to go down to 79.5 kg. So, working our own correction, we told him to get us down to 81.0 kg. Doing the math, that's 3.4 plus 0.4 for rinseback for a total of 3.8 kg to be removed. Cool. We walked out at 79.6 kg.

A differential of 1.5 kg is huge!!! It is the difference between an easy dialysis session (at 3.8 kg being
removed) and a much more difficult session (with 5.3 kg actually having been removed.)

[carolynt]

Alene, you are a wealth of knowledge.  I dialysis for three hours which I hope will last for a while since everyone seems to be longer.  You are right that I am not urinating as much as I use to so probably some of the weight loss is real water.  My BP drops really low so this is the other problem.  Thanks again I am now beginning to understand what kidney dialysis is all about with everyones responses to all my questions.  More questions to come.